Methods of forming a pattern on a substrate

ABSTRACT

A method of forming a pattern on a substrate includes forming longitudinally elongated first lines and first sidewall spacers longitudinally along opposite sides of the first lines elevationally over an underlying substrate. Longitudinally elongated second lines and second sidewall spacers are formed longitudinally along opposite sides of the second lines. The second lines and the second sidewall spacers cross elevationally over the first lines and the first sidewall spacers. The second sidewall spacers are removed from crossing over the first lines. The first and second lines are removed in forming a pattern comprising portions of the first and second sidewall spacers over the underlying substrate. Other methods are disclosed.

TECHNICAL FIELD

Embodiments disclosed herein pertain to methods of forming a pattern ona substrate, for example in the fabrication of integrated circuitry.

BACKGROUND

Integrated circuits are often formed on a semiconductor substrate suchas a silicon wafer or other semiconductive material. In general, layersof various materials which are semiconductive, conductive, orelectrically insulative are used to form the integrated circuits. By wayof examples, the various materials may be doped, ion implanted,deposited, etched, grown, etc. using various processes. A continuinggoal in semiconductor processing is to strive to reduce the size ofindividual electronic components, thereby enabling smaller and denserintegrated circuitry.

One technique for patterning and processing semiconductor substrates isphotolithography. Such may include deposition of a patternable maskinglayer commonly known as photoresist. Such materials can be processed tomodify their solubility in certain solvents, and are thereby readilyusable to form patterns on a substrate. For example, portions of aphotoresist layer can be exposed to actinic energy through openings in aradiation-patterning tool, such as a mask or reticle, to change thesolvent solubility of the exposed regions versus the unexposed regionscompared to the solubility in the as-deposited state. Thereafter, theexposed or unexposed regions can be removed, depending on the type ofphotoresist, to leave a masking pattern of the photoresist on thesubstrate. Adjacent areas of the underlying substrate next to the maskedportions can be processed, for example by etching or ion implanting, toeffect the desired processing of the substrate adjacent the maskingmaterial. In certain instances, multiple different layers of photoresistand/or a combination of photoresists with non-radiation sensitivemasking materials are used. Further, patterns may be formed onsubstrates without using photoresist.

The continual reduction in feature sizes places ever greater demands onthe techniques used to form those features. For example,photolithography is commonly used to form patterned features such asconductive lines and arrays of contact openings to underlying circuitry.A concept commonly referred to as “pitch” can be used to describe thesizes of the repeating features in conjunction with spaces immediatelyadjacent thereto. Pitch may be defined as the distance between anidentical point in two neighboring features of a repeating pattern in astraight-line cross section, thereby including the maximum width of thefeature and the space to the next immediately adjacent feature. However,due to factors such as optics and light or radiation wavelength,photolithography techniques tend to have a minimum pitch below which aparticular photolithographic technique cannot reliably form features.Thus, minimum pitch of a photolithographic technique is an obstacle tocontinued feature size reduction using photolithography.

Pitch doubling or pitch multiplication is one proposed method forextending the capabilities of photolithographic techniques beyond theirminimum pitch. Such typically forms features narrower than minimumphotolithography resolution by depositing one or more spacer-forminglayers to have a total lateral thickness which is less than that of theminimum capable photolithographic feature size. The spacer-forminglayers are commonly anisotropically etched to form sub-lithographicfeatures, and then the features which were formed at the minimumphotolithographic feature size are etched from the substrate.

Using such techniques where pitch is actually halved, the reduction inpitch is conventionally referred to as pitch “doubling”. More generally,“pitch multiplication” encompasses increase in pitch of two or moretimes, and also of fractional values other than integers. Thusconventionally, “multiplication” of pitch by a certain factor actuallyinvolves reducing the pitch by that factor.

In addition to minimum feature size and placement of such features, itis often highly desirable that the features as-formed be uniform indimension. Accordingly, uniformity when forming a plurality of featuresmay also be of concern, and is increasingly a challenge as the minimumfeature dimensions reduce.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic top view of a substrate in process inaccordance with an embodiment of the invention.

FIG. 2 is a cross-sectional view taken through line 2-2 in FIG. 1.

FIG. 3 is a view of the FIG. 1 substrate at a processing step subsequentto that shown by FIG. 1.

FIG. 4 is a cross-sectional view taken through line 4-4 in FIG. 3.

FIG. 5 is a view of the FIG. 3 substrate at a processing step subsequentto that shown by FIG. 3.

FIG. 6 is a cross-sectional view taken through line 6-6 in FIG. 5.

FIG. 7 is a view of the FIG. 5 substrate at a processing step subsequentto that shown by FIG. 5.

FIG. 8 is a cross-sectional view taken through line 8-8 in FIG. 7.

FIG. 9 is a cross-sectional view taken through line 9-9 in FIG. 7.

FIG. 10 is a view of the FIG. 7 substrate at a processing stepsubsequent to that shown by FIG. 7.

FIG. 11 is a cross-sectional view taken through line 11-11 in FIG. 10.

FIG. 12 is a cross-sectional view taken through line 12-12 in FIG. 10.

FIG. 13 is a cross-sectional view taken through line 13-13 in FIG. 10.

FIG. 14 is a view of the FIG. 11 substrate at a processing stepsubsequent to that shown by FIG. 11.

FIG. 15 is a view of the FIG. 12 substrate at a processing stepsubsequent to that shown by FIG. 12 and corresponding in processingsequence to that of FIGS. 14 and 16.

FIG. 16 is a view of the FIG. 13 substrate at a processing stepsubsequent to that shown by FIG. 13 and corresponding in processingsequence to that of FIGS. 14 and 15.

FIG. 17 is a view of the FIG. 10 substrate at a processing stepsubsequent to that shown by FIGS. 14, 15, and 16.

FIG. 18 is a cross-sectional view taken through line 18-18 in FIG. 17.

FIG. 19 is a cross-sectional view taken through line 19-19 in FIG. 17.

FIG. 20 is a cross-sectional view taken through line 20-20 in FIG. 17.

FIG. 21 is a cross-sectional view taken through line 21-21 in FIG. 17.

FIG. 22 is a cross-sectional view taken through line 22-22 in FIG. 17.

FIG. 23 is a view of the FIG. 17 substrate at a processing stepsubsequent to that shown by FIG. 17.

FIG. 24 is a cross-sectional view taken through line 24-24 in FIG. 23.

FIG. 25 is a cross-sectional view taken through line 25-25 in FIG. 23.

FIG. 26 is a view of the FIG. 23 substrate at a processing stepsubsequent to that shown by FIG. 23.

FIG. 27 is a cross-sectional view taken through line 27-27 in FIG. 26.

FIG. 28 is a cross-sectional view taken through line 28-28 in FIG. 26.

FIG. 29 is a view of the FIG. 26 substrate at a processing stepsubsequent to that shown by FIG. 26.

FIG. 30 is a cross-sectional view taken through line 30-30 in FIG. 29.

FIG. 31 is a view of the FIG. 29 substrate at a processing stepsubsequent to that shown by FIG. 29.

FIG. 32 is a cross-sectional view taken through line 32-32 in FIG. 31.

FIG. 33 is a view of the FIG. 31 substrate at a processing stepsubsequent to that shown by FIG. 31.

FIG. 34 is a cross-sectional view taken through line 34-34 in FIG. 33.

FIG. 35 is a view of a substrate showing alternate processing.

FIG. 36 is a cross-sectional view taken through line 36-36 in FIG. 35.

FIG. 37 is a view of a substrate showing alternate processing.

FIG. 38 is a cross-sectional view taken through line 38-38 in FIG. 37.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Example methods of forming a pattern on a substrate are initiallydescribed with reference to FIGS. 1-28 with respect to a substratefragment 10 and with reference to FIGS. 37 and 38 with respect to asubstrate fragment 10 a. Referring to FIGS. 1 and 2 and substratefragment 10, longitudinally elongated lines 12 have been formed over asubstrate 14. The material of lines 12 and the material of substrate 14,and other materials referred to herein, may be homogenous ornon-homogenous. As an example, substrate 14 may comprise bulkmonocrystalline silicon and/or a semiconductor-on-insulator substrate.As an additional example, substrate 14 may comprise dielectric materialhaving conductive contacts or vias therein which extend vertically orotherwise into electrical connection with electronic device components,regions, or material received elevationally inward of the dielectricmaterial. Substrate 14 may be a semiconductor substrate. In the contextof this document, the term “semiconductor substrate” or “semiconductivesubstrate” is defined to mean any construction comprising semiconductivematerial, including, but not limited to, bulk semiconductive materialssuch as a semiconductive wafer (either alone or in assemblies comprisingother materials thereon), and semiconductive material layers (eitheralone or in assemblies comprising other materials). The term “substrate”refers to any supporting structure, including, but not limited to, thesemiconductive substrates described above.

Only two lines 12 are shown for clarity in the figures, although likelythousands or millions of such lines may be fabricated over a substratearea of interest. Further, example lines 12 are shown as being ofconstant and equal width and height relative one another, as well asbeing equally spaced from one another by a distance equal to theirwidth. Alternate shapes, sizes and/or configurations can be used.

Example substrate 14 is shown as comprising a base substrate 16 (e.g.,semiconductor material) having material 18 and material 20 formedthereover. Material 20 may be used in forming a pattern over underlyingsubstrate 16/18.

Material 20 may comprise suitable masking material, for examplehard-masking material, and one or more antireflective coating materials.An example material 20 is a Si—O—N-comprising material formed to anexample thickness from about 50 Angstroms to about 500 Angstroms. Anexample material 18 is undoped polysilicon formed to an examplethickness from about 50 Angstroms to 2,000 Angstroms. Regardless, any ofmaterials 16, 18, and 20 may be conductive, dielectric, and/orsemiconductive.

Referring to FIGS. 3 and 4, lines 12 (not shown) have been laterallytrimmed to reduce their widths by half and then used as masking whileetching material 20, thereby forming longitudinally elongated firstlines 22 elevationally over an underlying substrate 16/18. Lines 12 (notshown) have been removed thereafter and/or during such etching. Greater,lesser, or no lateral trimming might be conducted of lines 12 (FIGS. 1and 2) in producing first lines 22 of FIGS. 3 and 4. Further, alternateor yet-to-be developed techniques may be used in producing first lines22. First lines 22 may be considered as respectively having oppositesides 23, tops 24 (i.e, elevationally outermost surfaces), and ends 25.Such are shown as being planar, with sides 23 being parallel one anotherand tops 24 of different lines being co-planar. Other constructions maybe used. Further, first lines 22 may be straight linear or non-linear(e.g. have multiple angled segments, curved segments, and/or becurvilinear, etc.), and may run parallel or non-parallel relative oneanother.

Referring to FIGS. 5 and 6, masking material 28 and masking material 30have been formed over first lines 22. Masking material 28 may be ofdifferent composition from that of material 20. As an example wherematerial 20 comprises a Si—O—N-comprising material, material 28 maycomprise carbon. In one embodiment, material 28 may be formed bydepositing and patterning a spin-on material, for example spin-oncarbon. Material 28 may be formed to greater, lesser, or equal thicknessas material 20 of first lines 22. Material 30 may comprise hard-maskingmaterial and/or one or more antireflective coatings and may be of thesame composition as material 20. Lines 32 (e.g., photoresist) have beenformed over and cross masking material 28/30. Such are shown as beingparallel and straight linear and cross first lines 22 orthogonally,although non-parallel, non-linear, non-orthogonally crossing, and/orother orientations and shapes may be used.

Referring to FIGS. 7-9, lines 32 (not shown) have been used as maskingwhile etching into hard-masking material 30 (not shown) and subsequentlyinto masking material 28 in forming lines 34 there-from. Lines 32 (notshown) and masking material 30 (not shown) have ultimately been removed.The etching to form lines 34 has ideally been conducted selectivelyrelative to material 20 of first lines 22. In the context of thisdocument, selectivity in an etch requires removal of one material at arate relative to another material of at least 2:1.

Referring to FIGS. 10-13, lines 34 (not shown) have been laterallytrimmed in forming longitudinally elongated second lines 36 which areelevationally over and cross first lines 22. FIGS. 10-12 show thelateral trimming being effective to reduce the width of lines 32 inFIGS. 7-9 by half, although greater, lesser, or no lateral trimming mayoccur. Further where lateral trimming does occur, such may occur withrespect to lines 32 of FIGS. 5 and 6 prior to or in addition to anylateral trimming of material 28 in lines 36. Alternate or additionaltechniques, whether existing or yet-to-be developed, may be used informing second lines 36 elevationally over and crossing first lines 22.Second lines 36 may be considered as respectively comprising oppositesides 37, tops 38 (i.e, elevationally outermost surfaces), and ends 39.Such are shown as being planar, with sides 37 being parallel one anotherand tops 38 of different lines being co-planar. Other constructions maybe used. Further, second lines 36 may be straight linear or non-linear(e.g. have multiple angled segments, curved segments, and/or becurvilinear, etc.), and may run parallel or non-parallel relative oneanother.

In one embodiment, second lines 36 are elevationally thicker betweenfirst lines 22 then atop of first lines 22, for example as is apparentin viewing FIGS. 11 and 12. Regardless, in one embodiment and as shown,underlying substrate 16/18 has a planar elevationally outermost surface17 over which first lines 22 and second lines 36 are received, with eachof the first and second lines extending to elevationally outermostsurface 17.

Referring to FIGS. 14-16, masking material 42 has been formed over tops24, 38, and sides 23, 37 of the crossing first and second lines 22, 36,respectively. Masking material 42 may also be formed over ends 25 and 39of the crossing first and second lines, as shown. In one embodiment,masking material 42 is formed to less-than-fill the void space that isbetween immediately adjacent second lines (i.e., a void space which isdefined elevationally by a maximum height of second lines 36 andlaterally by the space between immediately adjacent second lines 36).Masking material 42 will ideally be of a composition which enables firstlines 22 and second lines 36 to ultimately be selectively etchedrelative to masking material 42. Masking material 42 is shown as beingformed to a thickness which is less than an equal width of the first andsecond lines, although lesser or greater thickness may be used,including thickness that is substantially equal to width of the firstand second lines. Masking material 42 may be formed to a thickness thatis less than a minimum photolithographic feature dimension. Maskingmaterial 42 may be elevationally thicker between first lines 22 thanelevationally over first lines 22, for example as shown with respect tothickness T₁ (FIGS. 14 and 15) and thickness T₂ (FIG. 14). Maskingmaterial 42 is ideally deposited in a very conformal andthickness-controlled manner (e.g., by chemical vapor deposition oratomic layer deposition) to achieve precise control of feature width.

Referring to FIGS. 17-22, masking material 42 has been removed to exposetops 24, 38 of first lines 22 and second lines 36, respectively, and inone embodiment to expose all of second line tops 38. In one embodiment,such may be considered as forming first sidewall spacers 44longitudinally along opposite sides of first lines 22, and formingsecond sidewall spacers 46 longitudinally along opposite sides of secondlines 36, wherein the second lines and second sidewall spacers crosselevationally over the first lines and first sidewall spacers. Maskingmaterial 42 is shown without cross-hatching in FIG. 17 for betterclarity in showing first sidewall spacers 44 where such are beneath andcrossed by second sidewall spacers 46 in such figure. In one embodiment,for example as shown and described, the first and second sidewallspacers may be formed at the same time. The act of removing may be, byway of example, by anisotropic etching, and which may be maskless (i.e.,no mask being over the substrate during the act of removing). The firstsidewall spacers and/or the second sidewall spacers may be formed as arespective ring around the individual first and/or second lines, forexample as shown.

Referring to FIGS. 23-25, second sidewall spacers 46 have been removedfrom crossing over first lines 22. Cross-hatching of masking material 42in the top view of FIG. 23 is shown consistent with that of FIGS. 24 and25. In one embodiment and as shown, second sidewall spacers 36 extendcompletely between immediately adjacent first lines 22 after having beenremoved from crossing over first lines 22. Regardless, in one embodimentat least some of masking material 42 remains along sidewalls of secondlines 36 between immediately adjacent first lines 22. In one embodiment,the act of removing may also remove masking material 42 from beingreceived over all of ends 25 of first lines 22 (as shown), and in oneembodiment from being received over all of ends 39 of second lines 36(not shown). Regardless, the processing starting at the completion offorming the FIGS. 14-16 structure through and to producing a structuresuch as that shown in FIGS. 23-25 may occur in a continuous mannerwithout stopping to produce an intermediate structure like that of FIGS.17-22. For example where first sidewall spacers 44 and second sidewallspacers 46 are formed by anisotropic etching of a masking material, thatanisotropic etching may be started with respect to the structure ofFIGS. 14-16 and continued without stopping to proceed directly to thatof FIGS. 23-25. Nevertheless, in one embodiment, the first and secondsidewalls spacers are formed in such a continuous process even if onlytransiently.

Referring to FIGS. 26-28, first lines 22 (not shown) and second lines 36(not shown) have been removed in forming a pattern 49 which comprisesspaced regions 51 of masking material 42 over underlying substrate16/18. In one embodiment, spaced regions 51 comprise portions of firstsidewall spacers 44 and second sidewall spacers 46. In one embodiment,the spaced regions are generally rectangular in horizontal cross-section(i.e, viewed from top-down) having adjacent sides of unequal length. Inone embodiment and as shown, the rectangular spaced regions 51 havelonger sides that are more than three times length of the shorter sides.This results in part from masking material 42 being formed to have athinner lateral thickness along sidewalls of second lines 46 than thewidth of second lines 46. In one embodiment, the rectangular spacedregions are provided to be about three times length of the shortersides, for example as shown in FIGS. 37 and 38 with respect to analternate embodiment substrate fragment 10 a. Like numerals from theabove described embodiments have been used where appropriate, with someconstruction differences being indicated with the suffix “a”. FIGS. 37and 38 correspond in structure to that of FIGS. 26 and 27, respectively,but wherein masking material 42 in a resultant pattern 49 a has beenformed to be thicker and equal to width of second lines 36 (not shown)than in the example shown in the FIGS. 14-28 embodiment, thereby forminglaterally thicker first sidewall spacers 44 a and second sidewallspacers 46 a. Accordingly as shown, spaced rectangular regions 51 a havelonger sides that are about three times the length of the shorter sides.Longer sides less than three times the length of the shorter sides maybe achieved by forming laterally thicker first sidewall spacers (notshown). Regardless, spaced regions 51/51 a might be processed further,for example by being subject to lateral trimming.

Pattern 49 may be transferred in whole or in part to underlyingsubstrate 16/18, if desired, in a number of different manners. Further,second sidewall spacers 46 that were over the ends of second lines 36(not shown in FIGS. 26-28) may be removed or used in patterningunderlying substrate material. Further, if removed, such may occur priorto or commensurate with the processing of FIGS. 23-25. Regardless, FIGS.29 and 30 show example of subsequent processing where the end portionsof spacers 46 (not shown) have been removed, and a fill material 50 hasbeen formed laterally of masking material regions 51.

Referring to FIGS. 31 and 32, masking material regions 51 (not shown)have been removed in forming openings 54 in fill material 50. In oneembodiment, such may form a contact opening mask 56 which comprises fillmaterial 50.

Referring to FIGS. 33 and 34, contact opening mask 56 (not shown) hasbeen used while etching contact openings 58 into underlying substrate16/18, and has been removed.

In one embodiment, the pattern which is formed has a minimum featurewidth that is half of the half-pitch. For example, lines 34 in FIGS. 7-9may be considered as precursor second lines having a pitch P and a halfthereof designated as ½P. Precursor second lines 34 may be laterallytrimmed in forming second lines, for example as shown in FIGS. 10-13.Pattern 49 a in FIGS. 37 and 38 has a minimum feature width that is halfof the half-pitch ½P in FIG. 7 (i.e., ¼P).

FIGS. 35 and 36 shows alternate example processing to that shown byFIGS. 29-34 with respect to a subsequently processed substrate 10 b.Like numerals from the above-described embodiments have been used whereappropriate, with some construction differences being indicated with thesuffix “b”. In FIGS. 35 and 36, underlying substrate 16/18 has beenetched into using remaining of the first and second sidewall spacers 44,46 (e.g., spaced masking material regions 51) as an etch mask.

CONCLUSION

In some embodiments, a method of forming a pattern on a substratecomprises forming longitudinally elongated first lines and firstsidewall spacers longitudinally along opposite sides of the first lineselevationally over an underlying substrate. Longitudinally elongatedsecond lines and second sidewall spacers are formed longitudinally alongopposite sides of the second lines. The second lines and the secondsidewall spacers cross elevationally over the first lines and the firstsidewall spacers. The second sidewall spacers are removed from crossingover the first lines. The first and second lines are removed in forminga pattern comprising portions of the first and second sidewall spacersover the underlying substrate.

In some embodiments, a method of forming a pattern on a substratecomprises forming longitudinally elongated first lines elevationallyover an underlying substrate. Longitudinally elongated second lines andmasking material are formed longitudinally along opposite sides of thesecond lines. The second lines and the masking material crosselevationally over the first lines. The second lines and the maskingmaterial are elevationally thicker between the first lines thanelevationally over the first lines. The masking material is removed fromcrossing over the first lines while leaving at least some of the maskingmaterial along sidewalls of the second lines between immediatelyadjacent first lines. The first and second lines are removed in forminga pattern comprising spaced regions of the masking material over theunderlying substrate.

In some embodiments, a method of forming a pattern on a substratesequentially comprises forming longitudinally elongated first lineselevationally over an underlying substrate. Longitudinally elongatedsecond lines are formed elevationally over and cross the first lines. Amasking material is formed over tops and sides of the crossing first andsecond lines to less than fill void space between immediately adjacentsecond lines. The masking material is removed to expose the tops of thefirst and second lines. The first and second lines are removed informing a pattern comprising spaced regions of the masking material overthe underlying substrate.

In some embodiments, a method of forming a pattern on a substratesequentially comprises forming longitudinally elongated first lineselevationally over an underlying substrate. Longitudinally elongatedsecond lines are formed elevationally over and cross the first lines.The second lines are elevationally thicker between the first lines thanover tops of the first lines. Masking material is formed over tops,sides and ends of the crossing first and second lines to less than fillvoid space between immediately adjacent second lines. The maskingmaterial is removed from over all of the tops and all of the ends of thefirst and second lines while leaving at least some of the maskingmaterial along sidewalls of the second lines between immediatelyadjacent first lines. The first and second lines are removed in forminga pattern comprising spaced regions of the masking material over theunderlying substrate.

In compliance with the statute, the subject matter disclosed herein hasbeen described in language more or less specific as to structural andmethodical features. It is to be understood, however, that the claimsare not limited to the specific features shown and described, since themeans herein disclosed comprise example embodiments. The claims are thusto be afforded full scope as literally worded, and to be appropriatelyinterpreted in accordance with the doctrine of equivalents.

1. A method of forming a pattern on a substrate, comprising: forminglongitudinally elongated first lines and first sidewall spacerslongitudinally along opposite sides of the first lines elevationallyover an underlying substrate; forming longitudinally elongated secondlines and second sidewall spacers longitudinally along opposite sides ofthe second lines, the second lines and the second sidewall spacerscrossing elevationally over the first lines and the first sidewallspacers; removing the second sidewall spacers from crossing over thefirst lines; and removing the first and second lines in forming apattern comprising portions of the first and second sidewall spacersover the underlying substrate.
 2. The method of claim 1 comprisingforming the first sidewall spacers as a ring around the respective firstlines.
 3. The method of claim 1 comprising forming the second sidewallspacers as a ring around the respective second lines.
 4. The method ofclaim 1 wherein the first and second sidewall spacers are formed at thesame time.
 5. The method of claim 1 wherein forming the second sidewallspacers comprises depositing and subsequently anisotropically etching amasking material.
 6. The method of claim 5 wherein the removing of thesecond sidewall spacers from crossing over the first lines comprisescontinuing the anisotropically etching of the masking material withoutstopping the etching between the forming of the second sidewall spacersand the removing of the second sidewall spacers from crossing over thefirst lines.
 7. The method of claim 1 wherein the second sidewallspacers extend completely between immediately adjacent first lines afterthe removing of the second sidewall spacers from crossing over the firstlines.
 8. The method of claim 1 wherein the second lines areelevationally thicker between the first lines than atop the first lines.9. The method of claim 1 wherein the underlying substrate has a planarelevationally outermost surface over which the first and second linesare received, each of the first and second lines extending to theelevationally outermost surface.
 10. The method of claim 9 wherein thesecond lines are elevationally thicker between the first lines than atopthe first lines.
 11. The method of claim 10 comprising forming the firstand second lines to have respective planar elevationally outermostsurfaces, the elevationally outermost surfaces of the first lines beingcoplanar relative one another and the elevationally outermost surfacesof the second lines being coplanar relative one another.
 12. The methodof claim 1 comprising: after removing the first and second lines,forming fill material laterally of the portions of the first and secondsidewall spacers; removing remaining of the portions of the first andsecond sidewall spacers in forming a contact opening mask comprising thefill material; and using the contact opening mask while etching contactopenings into the underlying substrate.
 13. The method of claim 1comprising after removing the first and second lines, etching into theunderlying substrate using remaining of the first and second sidewallspacers as an etch mask.
 14. The method of claim 1 comprising formingpredecessor second lines which are laterally trimmed in forming thesecond lines, the predecessor second lines having a pitch and a halfthereof, the pattern having a minimum feature width that is half of thehalf-pitch.
 15. The method of claim 1 wherein the portions of the firstand second spacers in the pattern are generally rectangular inhorizontal cross-section having adjacent sides of unequal length. 16.The method of claim 15 wherein the rectangular portions have longersides that are about three times length of the shorter sides.
 17. Themethod of claim 15 wherein the rectangular portions have longer sidesthat are more than three times length of the shorter sides.
 18. A methodof forming a pattern on a substrate, comprising: forming longitudinallyelongated first lines elevationally over an underlying substrate;forming longitudinally elongated second lines and masking materiallongitudinally along opposite sides of the second lines, the secondlines and the masking material crossing elevationally over the firstlines, the second lines and the masking material being elevationallythicker between the first lines than elevationally over the first lines;removing the masking material from crossing over the first lines whileleaving at least some of the masking material along sidewalls of thesecond lines between immediately adjacent first lines; and removing thefirst and second lines in forming a pattern comprising spaced regions ofthe masking material over the underlying substrate.
 19. The method ofclaim 18 comprising forming the masking material longitudinally alongopposite sides of the first lines.
 20. The method of claim 18 comprisingforming the first and second lines to have respective planarelevationally outermost surfaces.
 21. The method of claim 20 wherein theelevationally outermost surfaces of the first lines are coplanarrelative one another and the elevationally outermost surfaces of thesecond lines are coplanar relative one another.
 22. The method of claim18 comprising forming the first and second lines to be of differentcompositions.
 23. The method of claim 18 wherein forming the secondlines comprises depositing and patterning a spin-on material.
 24. Amethod of forming a pattern on a substrate sequentially comprising:forming longitudinally elongated first lines elevationally over anunderlying substrate; forming longitudinally elongated second lineselevationally over and crossing the first lines; forming a maskingmaterial over tops and sides of the crossing first and second lines toless than fill void space between immediately adjacent second lines;removing the masking material to expose the tops of the first and secondlines; and removing the first and second lines in forming a patterncomprising spaced regions of the masking material over the underlyingsubstrate.
 25. The method of claim 24 wherein the removing of themasking material is from over all of the tops of the first and secondlines.
 26. A method of forming a pattern on a substrate sequentiallycomprising: forming longitudinally elongated first lines elevationallyover an underlying substrate; forming longitudinally elongated secondlines elevationally over and crossing the first lines, the second linesbeing elevationally thicker between the first lines than over tops ofthe first lines; forming a masking material over tops, sides and ends ofthe crossing first and second lines to less than fill void space betweenimmediately adjacent second lines; removing the masking material fromover all of the tops and all of the ends of the first and second lineswhile leaving at least some of the masking material along sidewalls ofthe second lines between immediately adjacent first lines; and removingthe first and second lines in forming a pattern comprising spacedregions of the masking material over the underlying substrate.
 27. Themethod of claim 26 wherein the removing of the masking material is byanisotropic etching.
 28. The method of claim 26 wherein the removing ofthe masking material is by mask-less anisotropic etching.